Democrats Gain Ground in South Dakota Federal Races

Democratic candidates drew a larger share of the vote in South Dakota's 2026 federal races than in the 2024 general election.

Updated on Nov. 10, 2026 in Political Parties

Democrats Gain Ground in South Dakota Federal Races

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Did you vote for a Democratic candidate in South Dakota's federal races?

Voters gave a greater percentage to federal Democratic candidates in the 2026 South Dakota general election than in 2024. Republican Marty Jackley won the U.S. House race over Democrat Nikki Gronli with 64% of the vote, while Republican Mike Rounds took 61% in the U.S. Senate race against Independent Brian Bengs.

Why it matters

The shift is measured against the 2024 general election, when Republican Dusty Johnson took 72% in the House race and Republican Donald Trump took 63% for president. Republicans still carried every federal race in the state, so the change is one of margin rather than outcome.

In the 2026 U.S. House race, Democrat Nikki Gronli received 36% of the vote, up from 28% for Democrat Sheryl Johnson in 2024. Republican Mike Rounds took 61% in the 2026 Senate race against Independent Brian Bengs at 39%, and the extraction does not explain what drove the shift.

The players

Marty Jackley

Marty Jackley is a Republican who won South Dakota's 2026 U.S. House race.

Nikki Gronli

Nikki Gronli is the Democratic candidate who lost South Dakota's 2026 U.S. House race to Marty Jackley.

Mike Rounds

Mike Rounds is a Republican who won South Dakota's 2026 U.S. Senate race.

Brian Bengs

Brian Bengs is the Independent candidate who lost South Dakota's 2026 U.S. Senate race to Mike Rounds.

The details

Republican Marty Jackley defeated Democrat Nikki Gronli in the 2026 U.S. House race, taking 64% to her 36%. In the same election, Republican Mike Rounds won the U.S. Senate seat with 61% over Independent Brian Bengs, who received 39%.

2024 general election: Dusty Johnson, Trump, and Harris vote totals recorded.
2026 general election: Jackley-Gronli House and Rounds-Bengs Senate results recorded.

Political Context

The 2024 general election, in which Trump took 63% and Dusty Johnson took 72% of the state's vote, set the baseline for measuring the 2026 results. The 2026 Democratic gains are measured against that baseline and remain within a state where Republicans still won every federal race.

For South Dakota voters, the results show Republican candidates still hold all federal seats in the state. The shift toward Democratic candidates is one of vote share, not of which party controls these offices.

The takeaway

Vote share can move even where outcomes stay the same, and comparing across election cycles shows how much margins have changed. Readers tracking South Dakota politics can watch whether the 2026 pattern holds in future contests.